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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

A utilização da resposta auditiva de estado estável para estimar limiares auditivos em indivíduos com perda auditiva neurossensorial / Utilization of auditory steady state response to estimate the auditory threshold in individuals with sensorineural hearing loss

Duarte, Josilene Luciene 26 March 2007 (has links)
O diagnóstico precoce da perda auditiva tem sido cada vez mais freqüente em virtude dos programas de saúde auditiva que estão sendo implantados em todo o país. Existe, contudo, a necessidade de técnicas e procedimentos que ajudem a identificar, com maior precisão, a presença e o grau da mesma. A Resposta Auditiva de Estado Estável (RAEE) é um procedimento eletrofisiológico que, ao contrário do Potencial Evocado Auditivo de Tronco Encefálico (PEATE) realizado com estímulo tone burst, possibilita avaliar, ao mesmo tempo limiares auditivos com especificidade por freqüência e por orelha, reduzindo assim o tempo do exame. Além disso, ele permite a estimulação até níveis próximos a 130 dBHL, podendo assim medir a audição residual. O objetivo deste estudo foi verificar a aplicabilidade da RAEE para determinar os limiares auditivos nos diferentes graus de perda auditiva neurossensorial. Foram avaliados 65 indivíduos com perda auditiva neurossensorial, sendo que 48 apresentaram alteração neurossensorial (coclear) de grau leve até profundo, e idades entre sete e 30 anos; e 17 apresentaram alteração neurossensorial (Neuropatia Auditiva/Dessincronia Auditiva) e idades entre 0,6 e cinco anos. A avaliação foi composta por Audiometria Tonal Liminar (ATL) e pesquisa da RAEE para o grupo com alteração neurossensorial (coclear) e somente a pesquisa da RAEE para o grupo com alteração neurossensorial (NA/DA). Os resultados demonstraram que, nos indivíduos com perda auditiva neurossensorial (coclear), houve associação significante (p<0,01) entre os limiares obtidos na ATL e RAEE para as freqüências de 0,5 a 4 kHz, ocorrendo uma maior concordância para graus de deficiências auditivas mais acentuadas. Já na perda auditiva neurossensorial (NA/DA), a RAEE mostrou ausência de resposta na maioria dos indivíduos avaliados. Concluímos que a RAEE pode predizer os limiares da ATL com maior precisão para os graus de perda auditiva mais acentuados, e que a utilização deste procedimento não mostrou informações adicionais que podem contribuir para o diagnóstico da perda auditiva neurossensorial (NA/DA). / The diagnosis of hearing loss in the first months of life has been increasingly frequent due to hearing health programs established throughout the country. Thus, techniques and procedures should be developed for accurate identification of the presence and severity of hearing loss, in a population whose motor and cognitive development does not allow response to behavioral methods. The auditory steady state response (ASSR) is an electrophysiological procedure which, different from the brainstem evoked response audiometry (BERA) conducted with tone burst stimuli, allows the establishment of hearing thresholds at multiple frequencies and for both ears, thus reducing the examination time. Moreover, it allows measurement of residual hearing due to the possibility of stimulation at levels close to 130 dBHL. Therefore, the present study aimed to investigate the applicability of ASSR for establishment of hearing thresholds in different severities of sensorineural hearing loss. A total of 65 individuals with sensorineural hearing loss were evaluated, among whom 48 presented mild to deep sensorineural disorder (cochlear), at the age range 7 to 30 years; and 17 presented sensorineural disorder (neuropathy/hearing dyssynchrony) aged 0.6 to 5 years. The evaluation comprised pure-tone threshold audiometry (PTTA) and ASSR analysis for the group with deep sensorineural disorder (cochlear) and only ASSR analysis for the group with sensorineural disorder (neuropathy/hearing dyssynchrony). The results demonstrated that, for individuals with deep sensorineural hearing loss (cochlear), there was significant association (p<0.01) between the thresholds obtained by PTTA and ASSR at frequencies from 0.5 to 4 kHz, with higher agreement in cases with more severe hearing loss. On the other hand, for the sensorineural hearing loss (neuropathy/hearing dyssynchrony), the ASSR was absent in most individuals analyzed. It was concluded that there is significant association between the thresholds obtained by PTTA and ASSR, and that the utilization of this procedure did not provide additional information that might contribute to the diagnosis of sensorineural hearing loss (neuropathy/hearing dyssynchrony), when compared to BERA
172

Força crítica, análise de parâmetros aeróbios e anaeróbios em exercício resistido - supino reto /

Meireles, Cláudio Luiz de Souza. January 2010 (has links)
Orientador: Claudio Alexandre Gobatto / Banca: Sérgio Cunha / Banca: Eduardo Kokubun / Banca: Sebastião Gobbi / Banca: Sérgio Eduardo de Andrade Perez / Resumo: O modelo de avaliação da potência crítica - Pcrit (Monod e Scherrer, 1965) é uma construção teórica, derivada da aplicação de uma série de testes, com cargas constantes até exaustão ou tempos limites (tlim). Muitos estudos têm examinado a aplicação e limitações metodológicas decorrentes da Pcrit em diferentes modalidades de exercícios cíclicos, mas poucos têm analisado as suas respostas aplicadas ao modelo de exercício resistido com peso (ERP). O objetivo geral deste estudo foi verificar a validade do modelo da Pcrit, como método de determinação da máxima fase estável de lactato (MFEL), aplicado ao ERP, no supino reto (SR) e verificar associações entre a capacidade de impulso anaeróbio (CIA), com a carga máxima (Cmax), média (Cmed) e índice de fadiga (IF) obtidos em testes anaeróbios de Wingate adaptado (WgtAd) no SR. Participaram da pesquisa 15 homens, fisicamente ativos em ERP, habituados com exercícios de intensidades elevadas [média (±) dp, idade de 21,33 ± 2,85 anos; massa corporal total de 78,48 ± 13,53 kg; estatura de 178,21 ± 7,44 cm e IMC de 24,63 ± 3,42 kg/m2]. Foram aplicados teste e re-teste de 1-RM, para determinação da carga máxima dinâmica em diferentes pegadas (padrão - PGP, aberta - PGA e fechada - PGF). Determinouse em PGP as cargas relativas a 30%, 40%, 50% e 60% para verificação dos tlim, os quais foram ajustados com procedimentos de regressão linear e não linear, determinando a força crítica (Fcrit) e a capacidade de impulso anaeróbio (CIA). Para a validade do parâmetro aeróbio, foi aplicado o teste de MFEL, levando em consideração três cargas de Fcrit (90%, 100% e 110%), e para o parâmetro anaeróbio, o teste de WgtAd com cargas diferenciadas da massa corporal total (MCT). A creatina quinase (CK), como marcador de lesão muscular, e a frequência cardíaca (FC), com variável hemodinâmica, foram analisadas para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The evaluation model of Critical Power - PCrit (Monod and Scherrer, 1965) is a theoretical construct, derived from the application of a series of tests with constant load until exhaustion or timeouts (tlim). Many studies have examined the application and methodological limitations arising PCrit into different types of cyclic exercise, but few have analyzed their responses applied to the model of Resistance Exercise with Weight (ERP). The aim of this study was to verify the validity of the model PCrit as a method of determining the Maximum Lactate Steady State (MLSS), applied to the ERP, the Bench Press (BP) and examine associations between the Anaerobic Capacity Boost (CIA) with the maximum load (Cmax), average (Cav) and Fatigue Index (FI) obtained in the Wingate anaerobic test adapted (WgtAd) in SR. Fifteen men participated in this study, physically active in the ERP, used to high exercise intensities [mean (±) SD, age 21.33 ± 2.85 years, total body mass of 78.48 ± 13.53 kg, height of 178.21 ± 7.44 cm and BMI 24.63 ± 3.42 kg/m2]. Were applied to test and re-test 1-RM to determine the maximum load dynamics in different footprints (default - PGP, open - PGA and closed - PGF). PGP was determined in the charges relating to 30%, 40%, 50% and 60% for verification of tlim, which were adjusted by regression procedures for linear and nonlinear, determining the Critical Force (Fcrit) and Anaerobic Capacity Boost (CIA). For the validity of the parameter aerobic test was applied to the MLSS, taking into consideration three loads Fcrit (90%, 100% and 110%), and for parameter anaerobic test WgtAd with different loads of Total Body Mass (MCT). Creatine Kinase (CK) as marker of muscle damage, and Heart Rate (HR), with a variable hemodynamics, were analyzed to determine the sensitivity regarding the volume and intensity imposed during and after the tests. It was concluded that the mathematical model... (Complete abstract click electronic access below) / Doutor
173

Metodologia para quantificação e acompanhamento de indicadores-chave de desempenho operacional

Giaquinto, Cláudia Daniela Melo January 2017 (has links)
Indicadores-chave de desempenho (KPIs) exercem um papel de extrema importância na indústria de processos, auxiliando na tomada de decisão. No entanto, para serem representativos precisam ser calculados de forma confiável. O presente trabalho propôs uma metodologia para o cálculo destes KPIs com base em técnicas de detecção do estado estacionário, remoção de ruído, propagação de erros e análise de sensibilidade. Estes KPIs foram apresentados, de acordo com o que consta na literatura, em uma nova ferramenta gráfica de acompanhamento proposta pelos autores, denominada StatSSCandlePlot. O StatSSCandlePlot apresenta os KPIs no padrão candlestick, que é bastante utilizado no mercado de ações, incluindo informações adicionais. O grande diferencial do StatSSCandlePlot é que os indicadores e suas respectivas propriedades exibidas são calculadas a partir de técnicas que englobam o tratamento de dados e análises estatísticas. A metodologia proposta foi aplicada em um estudo de caso de um chuveiro contendo dois princípios de aquecimento, gás e energia elétrica. Para este estudo, foi criado o Índice de Qualidade do Banho (IQB), que é um indicador dependente da temperatura e da vazão de saída, cujos dados foram avaliados em três cenários distintos, o primeiro quando o sistema é submetido a distúrbios na vazão, no segundo ocorre uma queda na temperatura da água fria e no último, o IQB foi avaliado quando o sistema foi submetido a distúrbios na vazão sob uma nova estratégia de controle da planta. A partir do StatSSCandlePlot, foi possível identificar as tendências do indicador nos diferentes cenários, a parcela de cada janela no estado estacionário, os valores a serem considerados do indicador e, de forma complementar, identificar a variável que mais influenciou na variação do indicador, através da análise de sensibilidade. / Key performance indicators (KPIs) play an extremely important role in the process industry, aiding in decision-making. However, to be representative they need to be calculated reliably. The present work proposed a methodology for the calculation of these KPIs based on steady state detection, noise removal, error propagation and sensitivity analysis techniques. These KPIs were presented, as far as it is known, in a new graphical KPIs monitoring tool proposed by the authors, called StatSSCandlePlot. StatSSCandlePlot introduces KPIs in the candlestick standard, which is widely used in the stock market, including additional information. The major difference of StatSSCandlePlot is that the indicators and their respective displayed properties are calculated from techniques that encompass data processing and statistical analysis. The proposed methodology was applied in a case study of a shower containing two principles of heating, gas and electric energy. For this study the Bath Quality Index (BQI) was created, which is a temperature and output flow dependent indicator, whose data were evaluated in three different scenarios, the first one when the system was submitted to flow disturbances, in the second one, a decrease in the temperature of the cold water and in the last one, the IQB was evaluated when the system was submitted to disturbances in the flow under a new strategy of control of the plant. From the StatSSCandlePlot, it was possible to identify the trends of the indicator in the different scenarios, the portion of each window in the steady state, the values to be considered in the indicator and, in a complementary way, to identify the variable that most influenced the variation of the indicator, through the sensitivity analysis.
174

Modélisation, simulation dynamique, validation expérimentale et optimisation énergétique d’une unité de rafraîchissement solaire par absorption / Modelling, dynamic simulation, experimental validation and energetic optimization of an absorption solar air-cooling system

Anies, Guillaume 28 November 2011 (has links)
Le rafraîchissement solaire constitue une alternative intéressante à la climatisation réalisée au moyen de machines frigorifiques à compression mécanique de vapeur dont l’alimentation est électrique. Parmi les différentes solutions susceptibles de convenir, l’utilisation d’un cycle frigorifique tri-therme permet une valorisation de chaleur solaire en énergie frigorifique et constitue une voie prometteuse. Cependant, la variabilité des conditions aux limites (météorologiques notamment) et de ses influences temporelles sur le comportement global rend, à ce jour, très difficile, l’évaluation des performances énergétiques du système et plus encore son dimensionnement optimal, compte tenu de l’absence de moyen d’investigation. Cette thèse introduit la problématique du sujet et analyse les différentes technologies de rafraîchissement solaire envisageables à l'heure actuelle, afin d'expliquer la forte prépondérance des systèmes à absorption. Ensuite, pour répondre au problème, une nouvelle méthode de modélisation de ces machines permettant la prédiction des performances en régime transitoire est introduite et appliquée à quatre machines du marché. Puis, une installation pilotede rafraîchissement solaire est présentée dans le but d'analyser et de comprendre son comportement dynamique, afin d'identifier des voies d'optimisation. Enfin, les résultats expérimentaux de cette installation sont utilisés dans le but de développer et valider un outil complet d'analyse et d'optimisation des performances, c'est à dire depuis le champ de capteurs jusqu'à la distribution de froid. Cet outil de modélisation de systèmes de rafraîchissement solaire pourra ensuite être valorisé par la mise au point d'une méthodologie d'aide au dimensionnement de ce type d'installation, destiné au décideur ou à l'ingénieur. / The general context of the thesis is the solar cooling. This is an interesting alternative to conventional air conditioning systems, that is to say systems using mechanical vapour compression from electric power. Among the various solutions that may be suitable, the use of a refrigeration tri-thermal cycle is a promising issue. However, given the lack of means of investigation, the variability of the boundary conditions (including weather) and its temporal influences on the overall behaviour makes it very difficult, to evaluate the energy performance of the system nowadays, and even more difficult its optimal sizing. This thesis introduces the issue of the subject and analyzes the different state-of-the-art solar cooling technologies in order to explain the strong predominance of absorption systems. Then, to address the problem, a new method of modelling of these machines for the prediction of transient performance is introduced and applied to four machines on the market. Then, a solar cooling pilot is presented in order to analyze and understand its dynamic behaviour, to identify ways of optimization. Finally, the experimental results of this plant are used in order to develop and validate a completeanalysis and performance optimization methodology, i.e. from the collector field to the cooling distribution. This modelling tool for solar cooling systems can then be enhanced by the development of a methodology to help the design of this type of installation, for the decision maker or for the engineer.
175

Determining lactate and glucose thresholds and heart rate deflection point in dogs undergoing incremental exercise testing / Determinação do limiar de lactato, limiar de glicose e o ponto de deflexão da frequência cardíaca em cães submetidos a teste de esforço

Zamora Restan, Wilmer Alejandro [UNESP] 22 February 2017 (has links)
Submitted by WILMER ALEJANDRO ZAMORA RESTAN null (alejomvz1208@gmail.com) on 2017-03-21T13:20:32Z No. of bitstreams: 1 Dissertação Final[924].pdf: 1300036 bytes, checksum: a71c43e8746de0b8643dcf3f0300ac03 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-03-22T14:28:53Z (GMT) No. of bitstreams: 1 zamorarestan_wa_me_jabo.pdf: 1300036 bytes, checksum: a71c43e8746de0b8643dcf3f0300ac03 (MD5) / Made available in DSpace on 2017-03-22T14:28:53Z (GMT). No. of bitstreams: 1 zamorarestan_wa_me_jabo.pdf: 1300036 bytes, checksum: a71c43e8746de0b8643dcf3f0300ac03 (MD5) Previous issue date: 2017-02-22 / O propósito deste estudo foi comparar métodos para determinação dos limiares relacionados com curvas de lactato plasmático e suas intensidades. Determinaram-se os limiares (1) de lactato (LTv) e (2) glicêmico (GTv) visualmente, (3) o limiar de lactato por meio do modelo polinomial (LTp), (4) limiar de glicose pelo modelo polinomial (GTp) e (5) o ponto de deflexão da frequência cardíaca (FCdp). Dezoito Beagles foram submetidos a teste de esforço incremental (IET). O IET foi realizado numa esteira, sendo concluído quando os cães mostraram sinais de fadiga. Os LTv GTv e FCdp foram determinados visualmente; LTp e GTp foram obtidos matematicamente por meio de função polinomial. Análise de variância (ANOVA), correlação de Pearson, regressão ordinária dos produtos mínimos e Bland-Altman foram utilizadas para avaliar a concordância entre as variáveis. Não houve diferença entre as velocidades relacionadas aos limiares (P >0.05). Houve correlação entre LTv e GTv (r = 0,91), LTv e LTp (r = 0,96), LT e GTp (r = 0,94) e a velocidade de corrida no ponto de deflexão da freqüência cardíaca (Vdp) e LT (r = 0,95 ) (P < 0,05). Foi observado viés constante entre LTv e LTp. Foi possível a determinação dos limiares de lactato e glicêmico em cães, sendo que a concordância entre LTv e FCdp indicou que a FC pode ser utilizada como método indireto para a obtenção do limiar de lactato. / The aim of this study was to compare methods to determining visually (1) lactate threshold (LTv), (2) glycemic threshold (GTv) and (3) lactate threshold by the polynomial model (LTp), (4) glucose threshold by the polynomial model (GTp), and (5) heart rate deflection point (HRdp). Eighteen Beagles underwent an incremental exercise testing (IET). IET was performed on the treadmill. The IET was completed when the dogs showed signs of fatigue. The LTv, GTv and HRdp were determined visually; LTp and GTp were obtained from the polynomial function. One-way analysis of variance, Pearson correlation, ordinary least product regressions and Bland-Altman plot were used to assess the agreement between the variables. There was no difference between the velocities corresponding to the thresholds (P >0,05). There was a correlation between LTv and GTv (r = 0.91), LTv and LTp (r = 0.96), LT and GTp (r = 0.94) and the running speed at the heart rate deflection point (Vdp) and LT (r = 0.95) (p <0.05). A constant bias was observed between LTv and LTp. It was possible to determine the lactate and glycemic thresholds in dogs, and the agreement between LTv and FCdp indicated that the HR can be used as an indirect method to obtain the lactate threshold.
176

Engenharia de interações seletivas para a geração de estados estacionários do campo de radiação / Engineering selective interactions for generating of nonclassical steady-state of the radiation field

Wilson Enrique Rosado Mercado 20 February 2015 (has links)
Neste trabalho, descrevemos vários protocolos para a geração de estados estacionários não clássicos, suportados principalmente pela engenharia de hamiltonianos seletivos Jaynes-Cummings, e de reservatórios atômicos. Começamos apresentando um protocolo para engenhar interações seletivas lineares e não lineares do tipo Jaynes-Cummings como também simulações numéricas para comprovar a eficácia de nosso esquema. Analisamos também como aplicar essas interações seletivas à preparação e proteção de estados de Fock estacionários via reservatório atômico. Esta estratégia combina a ação dos mecanismo de amortecimento da cavidade com os de um reservatório atômico engenhado para conduzir uma distribuição térmica inicial a um estado de Fock estacionário. A mesma técnica pode ser utilizada para fatiar as distribuições de probabilidade no espaço de Fock, permitindo assim a preparação de uma variedade de estados de equilíbrio não clássicos. Também apresentamos um protocolo para a engenharia de interações upper-bound e sliced Jaynes-Cummings e anti-Jaynes-Cummings na eletrodinâmica quântica de cavidade. No Hamiltoniano upper-bound, a interação átomo-campo está confinada a um subespaço de Fock com estados que vão desde &Iota;0&gt; até &Iota;4&gt; enquanto que no Hamiltoniano sliced vão desde &Iota;M&gt; até &Iota;M + 4&gt;. Mostramos como construir Liouvillianos upper-bound independentemente da engenharia do Hamiltoniano upper-bound. Os Hamiltonianos e Liouvillianos upper-bound e sliced podem ser usados, entre outras aplicações, para gerar estados de Fock estacionários no modo da cavidade e para a implementação de um dispositivo de tesoura quântica para truncagem de estado óptico. Finalmente, propomos um esquema para a preparação de estados emaranhados estacionários em redes bosônicas dissipativas. Descrevemos a sua aplicação em um sistema de cavidades acopladas interagindo com um reservatório construído por átomos de três níveis. Os emblemáticos estados Bell e NOON, e estados multipartites (tipo W) podem ser produzidos com alta fidelidade e pureza. / In this work, we describe various protocols for the generation of nonclassical steady-state, supported mainly by the engineering selective Hamiltonian Jaynes-Cummings-type, and atomics reservoirs. We started presenting a framework to engineer nonlinear selective JaynesCummings-type interactions with numerical simulations to prove the effectiveness of our scheme. We further analyses how to apply these selective interactions to the preparation and protection of steady Fock states via atomic reservoir. This strategy combines the action of cavity damping mechanisms with that of an engineered atomic reservoir to drive an initial thermal distribution to a Fock equilibrium state. The same technique can be used to slice probability distributions in the Fock space, thus allowing the preparation of a variety of non-classical equilibrium states. Also we present a protocol to engineer upper-bound and sliced Jaynes-Cummings-type and anti-Jaynes-Cummings-type Hamiltonians in cavity quantum electrodynamics. In the upper-bounded Hamiltonians, the atom-field interaction is confined to a subspace of Fock states ranging from &Iota;0&gt; up to &Iota;4&gt;, while in the sliced interaction the Fock subspace ranges from &Iota;M&gt; up to &Iota;M + 4&gt;. We also show how to build upper-bounded and sliced Liouvillians irrespective of engineering Hamiltonians. The upper-bounded and sliced Hamiltonians and Liouvillians can be used, among other applications, to generate steady Fock states of a cavity mode and for the implementation of a quantum-scissors device for optical state truncation. Finally we propose a scheme for the preparation of steady entanglements in bosonic dissipative networks. We describe its implementation in a system of coupled cavities interacting with an engineered reservoir built up of three-level atoms. Emblematic bipartite (Bell and NOON) and multipartite (W -class) states can be produced with high fidelity and purity.
177

Análise de existência de máxima fase estável de lactato em exercício resistido em população jovem e idosa / Maximal lactate steady analysis in resistance exercise in young and older groups

Nuno Manuel Frade de Sousa 27 October 2010 (has links)
A máxima fase estável do lactato (MFEL) é considerada uma intensidade critica em exercício dinâmico e sua intensidade é específica do grupo etário. No entanto, apesar da relação existente entre a intensidade de esforço e os ajustes cardiovasculares, metabólicos e ventilatórios durante o exercício resistido, a MFEL foi muito pouco estudada neste tipo de exercício. O objetivo do estudo foi verificar e comparar a existência de MFEL nos exercícios leg press (LP) e supino reto (SR) em dois grupos: jovens e idosos. Além disso, analisar o comportamento das variáveis ergoespirométricas (VE, VO2 e VCO2), lactacidemia, freqüência cardíaca (FC), pressão arterial (PA) e percepção subjetiva de esforço (PSE) na intensidade da MFEL. Foram avaliados 13 homens jovens (26,1 +/- 2,9 anos) e 11 idosos (68,9 +/- 4,0 anos) saudáveis e com experiência mínima de 6 meses em treinamento resistido, que passaram por teste de 1 repetição máxima (1RM), teste crescente para determinação do limiar anaeróbio (LAn) e mais três sessões para a determinação da MFEL. Todas as sessões foram realizadas no mesmo horário do dia, separadas por 48 a 72 horas de intervalo. O LAn, expresso em %1RM, foi significativamente superior no LP em relação ao SR para os dois grupos estudados (LP: 27,8 +/- 3,6 %1RM nos jovens e 27,9 +/- 5,0% 1RM nos idosos; SR: 24,0 +/- 3,0% 1RM nos jovens e 21,5 +/- 3,1% 1RM nos idosos). Não foram observadas diferenças estatisticamente significativas na intensidade do LAn entre os grupos em cada aparelho. A lactacidemia na intensidade do LAn foi significativamente inferior no LP (1,86 +/- 0,63 mmol/L nos jovens e 1,23 +/- 0,34 mmol/L nos idosos) em relação ao SR (2,08 +/- 0,41 mmol/L nos jovens e 1,91 +/- 0,40 mmol/L nos idosos). A intensidade da MFEL no grupo de jovens foi 29,2 +/- 6,7% 1RM no LP e 21,7 +/- 4,4% 1RM no SR. No grupo e idosos, a MFEL ocorreu a 30,9 +/- 4,9% 1RM no LP e 23,3 +/- 6,6% 1RM no SR. A MFEL ocorre em intensidade significativamente menor no aparelho SR para os dois grupos (p < ou = 0,05), sem diferenças estatisticamente significativas entre os grupos. Não houve diferença significativa entre as intensidades do LAn e da MFEL para os dois grupos nos dois aparelhos. Durante a realização do exercício na MFEL, ocorreu a estabilização dos parâmetros ergoespirométricos, FC, PA e PSE entre a série 9 e série 15. Estes resultados demonstram que é possível determinar MFEL nos exercícios LP e SR para as duas populações estudadas. A MFEL ocorre em intensidades superiores no exercício LP. A intensidade da MFEL, expressa em percentual de 1RM, é semelhante à intensidade do LAn. / The maximal lactate steady state (MLSS) is considered a critical intensity of dynamic exercise and its intensity is specific to the age group. However, despite the relationship between exercise intensity and cardiovascular, metabolic and ventilatory adjustments during resistance exercise, the MLSS was unknown in this type of exercise. The purpose of the study was to verify and to compare if there is a maximal lactate steady state (MLSS) for leg press (LP) and bench press (BP) exercises in two different groups: young and older people. Furthermore, to evaluate the ventilatory responses (VE, VO2 e VCO2, blood lactate concentration (BLC), heart rate (HR), blood pressure and rate of perceived exertion (RPE) to those exercises performed on MLSS intensity. 13 young men (26,1 +/- 2,9 years) and 11 elderly healthy men (68,9 +/- 4,0 years) with a minimal experience of 6 months of resistance training volunteered for the study. Volunteers underwent a 1 repetition maximum test (1RM), an incremental test to determine anaerobic threshold (AT) and three more sessions to determine MLSS. Session were performed on the same time of day and separated by a 48-72 h interval. AT intensity (%1RM) was significantly higher for LP than BP for the two groups studied (LP: 27,8 +/- 3,6% 1RM for young group and 27,9 +/- 5,0% 1RM for elderly; BP: 24,0 +/- 3,0%1RM for young group and 21,5 +/- 3,1%1RM for elderly). There was no significant difference between groups in the AT intensity. BLC on AT was significantly lower for LP (1,86 +/- 0,63 mmol/L for young group and 1,23 +/- 0,34 mmol/L for elderly) than BP (2,08 +/- 0,41 mmol/L for young and 1,91 +/- 0,40 mmol/L for elderly). MLSS intensity for young group was 29,2 +/- 6,7% 1RM in LP and 21,7 +/- 4,4% 1RM in BP. For elderly, MLSS was 30,9 +/- 4,9% 1RM in LP and 23,3 +/- 6,6% 1RM in BP. MLSS intensity was significantly lower in BP for both groups (p < or = 0,05), with no statistical differences between groups. There was no significant difference between AT and MLSS intensities on both groups. During exercise on MLSS, ventilatory parameters, HR, blood pressure and RPE stabilized between set 9 and set 15. These results show that it is possible to identify MLSS on the LP and BP exercises for both populations. MLSS intensity is higher in LP exercise, when compared to BP. MLSS intensity is similar to the AT intensity.
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Natureza e crescimento econômico : como uma mudança de paradigma pode contribuir para uma economia ecologicamente responsável

Schütz, Felipe January 2017 (has links)
O presente trabalho discute como uma mudança de paradigma econômico pode contribuir para uma economia ecologicamente responsável. Em linha com esse propósito num primeiro momento são apresentados os sinais da necessidade dessa mudança. Nessa primeira parte são apresentadas algumas das insuficiências das ferramentas econômicas tradicionais para uma harmonização com o meio ambiente. Num segundo momento são discutidas ideias alternativas para a abordagem da relação entre crescimento econômico e meio ambiente: economia e entropia, estado estacionário e prosperidade sem crescimento. Nessas discussões foi dada ênfase aos estudos dos economistas Nicholas Georgescu-Roegen, Herman Daly e Timothy Jackson. Na parte seguinte são discutidas as implicações éticas para o desenvolvimento de um modelo econômico ecologicamente responsável. Por fim, por meio do estudo da Comissão Stiglitz-Sen-Fitoussi, do Índice de Progresso Social e de Índices de Felicidade argumenta-se como novas medidas de desenvolvimento econômico, social e ambiental podem contribuir para um paradigma econômico ecologicamente responsável. / This study discuss how a change of economic paradigm could contribute to an environmentally responsible economy. In order to do this, at first, the signs of the need for this paradigm shift are presented. On this matter the shortcomings of traditional economic tools for harmonization with the environment are analysed. Secondly, alternative ideias to address the relationship between economic growth and the environment, such as economy and entropy, steady state, and prosperity without growth are discussed. In these discussions the studies of economists like Nicholas Georgescu-Roegen, Herman Daly and Timothy Jackson, are emphasized. In the next part of this study the ethical implications for the development of an environmentally responsible economic model are approached. Finally, through the study of the Stiglitz-Sen-Fitoussi Comssion, the Social Progress Index and Happiness Index, it is shown how new measures of economic, social and environmental development could contribute to an environmentally responsible economic paradigm.
179

Development of New Monte Carlo Methods in Reactor Physics : Criticality, Non-Linear Steady-State and Burnup Problems

Dufek, Jan January 2009 (has links)
The Monte Carlo method is, practically, the only approach capable of giving detail insight into complex neutron transport problems. In reactor physics, the method has been used mainly for determining the keff in criticality calculations. In the last decade, the continuously growing computer performance has allowed to apply the Monte Carlo method also on simple burnup simulations of nuclear systems. Nevertheless, due to its extensive computational demands the Monte Carlo method is still not used as commonly as deterministic methods. One of the reasons for the large computational demands of Monte Carlo criticality calculations is the necessity to carry out a number of inactive cycles to converge the fission source. This thesis presents a new concept of fission matrix based Monte Carlo criticality calculations where inactive cycles are not required. It is shown that the fission matrix is not sensitive to the errors in the fission source, and can be thus calculated by a Monte Carlo calculation without inactive cycles. All required results, including keff, are then derived via the final fission matrix. The confidence interval for the estimated keff can be conservatively derived from the variance in the fission matrix. This was confirmed by numerical test calculations of Whitesides's ``keff of the world problem'' model where other Monte Carlo methods fail to estimate the confidence interval correctly unless a large number of inactive cycles is simulated.   Another problem is that the existing Monte Carlo criticality codes are not well shaped for parallel computations; they cannot fully utilise the processing power of modern multi-processor computers and computer clusters. This thesis presents a new parallel computing scheme for Monte Carlo criticality calculations based on the fission matrix. The fission matrix is combined over a number of independent parallel simulations, and the final results are derived by means of the fission matrix. This scheme allows for a practically ideal parallel scaling since no communication among the parallel simulations is required, and no inactive cycles need to be simulated.   When the Monte Carlo criticality calculations are sufficiently fast, they will be more commonly applied on complex reactor physics problems, like non-linear steady-state calculations and fuel cycle calculations. This thesis develops an efficient method that introduces thermal-hydraulic and other feedbacks into the numerical model of a power reactor, allowing to carry out a non-linear Monte Carlo analysis of the reactor with steady-state core conditions. The thesis also shows that the major existing Monte Carlo burnup codes use unstable algorithms for coupling the neutronic and burnup calculations; therefore, they cannot be used for fuel cycle calculations. Nevertheless, stable coupling algorithms are known and can be implemented into the future Monte Carlo burnup codes. / QC 20100709
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CFD analysis of steady state flow reaction forces in a rim spool valve

Okungbowa, Norense Stanley 20 February 2006
Hydraulic spool valves are found in most hydraulic circuits in which flow is to be modulated. Therefore their dynamic performance is critical to the overall performance of the circuit. Fundamental to this performance is the presence of flow reaction forces which act on the spool. These forces can result in the necessity of using two stage devices to drive the spool and in some cases have been directly linked to valve and circuit instabilities. As such, a great deal of research and design has concentrated on ways to reduce or compensate for flow forces. In one particular series of studies conducted on flow divider valves, it was established that a rim machined into the land of the spool reduced the flow dividing error by approximately 70-80%, and it was deduced that the main contribution to this error was flow forces. Direct verification of the claim regarding flow force reduction was not achieved and hence was the motivation for this particular study. <p> This thesis will consider the reaction (flow) force associated with a conventional spool land and one with a rim machined into it, and a modified form of the rimmed land referred to as a sharp edge tapered rim spool land. The rim and the sharp edge tapered rim were specially designed geometrical changes to the lands of the standard spool in order to reduce the large steady state flow forces (SSFF) inherent in the standard spool valve. In order to analyze the flow field inside the interior passages of the valve, three configurations of the spool were considered for orifice openings of 0.375, 0.5, 0.75 and 1.05 mm. Computational Fluid Dynamics (CFD) analysis was used to describe the fluid mechanics associated with the steady state flow forces as it provided a detailed structure of the flow through the valve, and to identify the flow mechanism whereby flow forces are reduced by the machining of a rim and tapered rim on the land of the spool. For all openings of the spool, the sharp tapered rim valve provides the largest reduction in SSFF. It was also observed that for all cases studied, the inflow SSFFs were smaller than for the outflow conditions. <p>The prediction of the steady state flow force on the rim spool was investigated in a flow divider valve configuration, and the results from the CFD analysis indicated a reduction by approximately 70%.

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